A timeline of Turkey's constitutional history

A historic referendum on constitutional changes in Turkey on April 16 will ask the electorate to vote on whether to approve an 18-article bill. Turkish citizens will decide to vote 'Yes' or 'No'. But it's not the nation's first major shift in governance nor amendments made to the constitution.

Here's a timeline of Turkey's constitutional history:

1808

Charter of Alliance; an agreement between the central government of the Ottoman Empire and local rulers restricted the authority of sultan.

1876

Ottoman constitution of 1876, the beginning of the constitutional era in Turkey.

1909

Revisions to the existing constitution.

1921

First constitution of the Republic of Turkey.

1924

The new constitution, considered to be less democratic than the previous:

- No separation of powers. Executive and judiciary were also under parliament's control

- De facto, no multiparty system

1928

Religious remarks removed from the constitution

1931

Fiscal amendments

1934

Universal suffrage begins

1937

Republican People's Party's (CHP) principles imposed on the constitution through the amendment

1960

Military coup d'etat in Turkey, known as '27 May coup.'

1961

Constitution instated after the coup. It introduced the bicameral system

- The executive branch is left to president and the council of ministers

- The judiciary branch is left to impartial courts. Supreme Board of Judges and Prosecutors established

- Supreme Court is established

- Unions, labour agreements and strikes are allowed

1971

March 12 Memorandum

1972

Council of Ministers were given the authority to issue decrees

- Civil servants' right to establish unions was abolished

- Autonomy of universities weakened

- State security courts with expanded jurisdiction were established

1980

September 12 coup d'état

1982

Another constitution instated after a coup. Unicameral system reinstated.

- Executive branch is empowered

- The focus shifted from the people to the state as opposed to previous constitutions.

1982

- Voting age lowered to 19

- The number of MPs increased to 450 from 400

- Bans on certain leaders abolished

1993

Restrictions on setting up TV and Radio stations eased

1995

Freedom to set up unions for civil servants

- Workers and public servants were given right to labour agreements

- Voting age further lowered to 18

- The ban on political parties to establish women and youth branches abolished

- Academics and university students were given right to be members of political parties

- The number of MPs increased to 550

1997

Coup d'état (Postmodern coup)

1999

Military members of the State Security Court replaced by civilians

- Privatisation of state properties allowed

2001

Crucial changes in line with European Court of Human Rights

- Freedom of communication included in the text

- Gender equality fortified

- Closing political parties made more difficult

2005

Changes in the structure of the Radio and Television High Council

2006

Age of candidacy for MP decreased to 25 from 30

2007

E-memorandum

2007

Changes through referendum

- Elections to be held every four years instead of five

- The president is to be elected through popular vote.

- Presidential elections to be held every five years instead of seven. This did not apply to the incumbent Abdullah Gul.

2010

Changes through referendum

- Changes in the structure of judiciary and courts.

2014

Recep Tayyip Erdogan becomes the first president of Turkey directly elected through popular vote.

2016

July 15 attempted coup d'état.